TS EAMCET · Physics · Semiconductors
The band gap in a semi-conductor is \(0.6 \mathrm{eV}\). The maximum wavelength of electromagnetic radiation which can create a hole-electron pair in this semiconductor is equal to [Use \(h c=1242 \mathrm{eV}-\mathrm{nm}\) ]
- A \(2450 \mathrm{~nm}\)
- B \(1150 \mathrm{~nm}\)
- C \(2070 \mathrm{~nm}\)
- D \(1050 \mathrm{~nm}\)
Answer & Solution
Correct Answer
(C) \(2070 \mathrm{~nm}\)
Step-by-step Solution
Detailed explanation
We have \[ \lambda_{\mathrm{o}}=\frac{1242}{0.6}=2070 \mathrm{~nm} \] If \(\lambda\) is greater than \(\lambda_0\), then energy of photon will be less than \(0.6 \mathrm{eV}\). So, electron hole pair will not generate. So, \(\lambda_0=2070 \mathrm{~nm}\) is maximum wavelength.
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